1. Field of the Invention
The present invention relates generally to electrical enclosures and, more particularly, to a cover assembly for an electrical enclosure, such as a panelboard or other load carrier. The invention also relates to electrical enclosures employing a cover assembly.
2. Background Information
Electrical equipment (e.g., without limitation, relays; circuit breakers; electric meters; transformers) are typically housed within an enclosure, such as, for example, a housing, such as a box or cabinet, in order to restrict access to the electrical equipment thereby resisting potential injury, and to resist unauthorized tampering with the electrical equipment, in general.
Such electrical enclosures include, for example, panelboards or other load centers which are designed to be secured to the wall of a building. Specifically, panelboards are known to be mounted either on the exterior surface of the wall or within a prepared opening in the wall (e.g., flush mounted panelboards, wherein the front panel of the panelboard is flush with respect to the surface of the wall). In either case, the panelboard typically includes a back panel and two sidewalls, a bottom wall and a top wall extending outwardly from the back panel in order to define a front opening and thus form the housing. The electrical equipment is mounted within the housing and a front panel, or cover assembly, is coupled to the sidewalls and/or the top and bottom walls in order to cover the front opening.
A variety of electrical enclosure front panels, or covers, have been developed in an attempt to achieve an optimum balance between the generally conflicting design objectives of permitting quick and easy access to the electrical equipment housed within the enclosure, while simultaneously resisting unauthorized access to the interior of the enclosure. Unauthorized access must be sufficiently restricted in order to prevent, for example, injury (e.g., electrical shock) or vandalism of the electrical equipment. However, the cover must also sufficiently enable authorized access to the enclosed electrical equipment relatively quickly in order to, for example, promptly reset a tripped circuit breaker or to perform routine maintenance. Still further complicating the design of electrical enclosure front covers, is the additional consideration of appearance. It is desirable that the resulting design be aesthetically pleasing.
Some electrical enclosures employ a removable front panel cover design. However, such panels are typically one-piece and can, therefore, be large and cumbersome to handle. The removable panels are also typically secured to the walls of the housing using a plurality of fasteners, such as screws or bolts. Accordingly, the panel requires the use of a separate tool, such as a screw-driver, in order to open and re-close the electrical enclosure. Not only is the need to remove numerous fasteners time-consuming and inefficient, but such a design also permits any individual in possession of a screw driver, or other suitable tool, to simply remove the fasteners connecting the panel to the enclosure, in order to gain access to the interior of the enclosure.
A number of hinged cover assemblies have been developed in an attempt to overcome the undesirable requirement of entirely removing the front panel. Such designs typically include a single hinge, such as a piano hinge, or a number of separate hinges which are attached to one of the sidewalls of the housing and to an edge of the front panel, thereby forming a hinged door. The hinged door is operable between an open position, in which the door is pivoted outwardly, away from the enclosure, thereby providing access to the interior of the enclosure, and a closed position in which the door abuts the enclosure and the interior of the enclosure is inaccessible. Most hinged door designs also employ a lock, in order to address the issue of undesired access to the interior of the enclosure. However, the door hinge mechanism is typically exposed thus permitting the lock to be bypassed and the enclosure to be opened by, for example, removing the hinge pins of the hinges attaching the door. The exposed hinges also detract from the aesthetic appeal of the enclosure.
Additional disadvantages of known panelboard door designs include the fact that they generally require a peripheral trim or a door catch which must be fastened to the walls of the enclosure by a plurality of mechanical fasteners. They also require the entire panel, or door, to be opened. In addition to the relatively large size of the entire panel, which can be cumbersome and awkward to open, opening the entire front panel exposes the top edges of the walls of the housing, which can be sharp and could, therefore, injure (e.g., cut) an individual attempting to gain access to the enclosure. Moreover, the mechanical fasteners securing the panel or trim to the walls can be removed, creating the possibility of the entire cover assembly being removed in order to gain unauthorized access to the interior of the enclosure.
There is room, therefore, for improvement in electrical enclosures and in cover assemblies for electrical enclosures.